| Diesel engine is the most important power unit for the vehicles in nowadays, fuel supply system is extremely crucial. Its design and manufacture requirements are very high, the fuel supply system design of the diesel engine is one of the important contents in engine design, its working condition and extent have an direct effect on the crucial performance such as indexing emission, noise, dynamic, economy, durability and etc. Especially nowadays, diesel engine technology are developed very quickly to meet the strict emission standards, so the fuel supply system of the diesel engine are continually developed also. In order to adapt the fuel supply system to the technology development, a perfect design method of the fuel supply system should be established, it is significant to expedite the develop period, guide the design, unit the science and technology effectually.The study concluded that the fuel supply system design of the diesel engine includes several stages:1.Concept design;2.Project design; 3.Project check up; 4.Project decision; 5.Technical design; 6.Drawing design; 7.Drawing check up; 8.Design validation; 9.Start of production.In the concept design, a fuel supply system type is selected from the existing systems according to the engine level. The engine level indicates the develop purpose of the engine, emission standards, engine performance and potential ability, and fuel supply system technology plays the leading role in meeting the present and future regulations. Concept decision is decided by the whole strategic target of the corporation, market guidance, domestic resource, develop difficulty and etc. In the project design stage, a whole fuel system sketch map should be designed and carried through the fuel injection pump type, calculated the fuel volume per stroke, plunger diameter, lift range according to the formular and experience, fixed form of the fuel injection pump should be designed also. For the fuel injector, select the nozzle to match tests, then make a result. Calculate and select the inner diameter of high-pressure fuel line in reason, design its shape according to the engine layout, and expansion length is equal respectively. Represent a technical report that the content includes important structure and performance data of the fuel supply system, fulfill the project checkup, make the decision, implement the technical design, the conclusion of the technical design is drawn through the match test between the fuel injection system and the engine without reference. Drawing design is a bridge linked the development and production, the drawing design needs to face quality, assemble and production. The prototype are manufactured in terms of the drawings passed the validation. After the test validation, release the drawings, make the mass production.A fuel supply system design method and process is quantized summarized through a case that CA1253P7K1L11T1 truck matching the BF6M1013-28 diesel engine. Engine BF6M1013-28 is a power assembly whose emission will meet the Europe 2,Europe 3 emission regulations, also have Europe 4 potential developed by china First Automobile Works for heavy-duty trucks and bus chassis. It is an advantaged engine model in the domestic market. In the concept design stage, unit injector series, unit pump system and common rail system performance comparisons are drawn, and evaluated the strategic and cost points, combined the vehicle strategic situation in First Automobile Works simultaneously, drawn a conclusion that use unit pump fuel supply system in the engine at last. So the fuel supply system sketch map is designed for the BF6M1013-28 engine. According to the engine develop target, the design essentials of the unit pump, fuel injector, high-pressure fuel line and fuel feed pump are summarized. The theoretic fuel supply volume per cycle of the fuel injection pump is calculated as per the engine power and fuel-consumption, the fuel injection pump plunger diameter and lift range is made as per the previous step, the plunger diameter, lift range, maximum fuel injection volume at maximum torque and rated speed condition, allowable speed of the camshaft are finally defined based on the product experience of fuel injection pump and fuel injector industry. The total flow area of the engine should be calculated in the fuel injector design process, select injection hole number, calculate the diameter, select the best version as per the engine test, the fixed form of the fuel injector is designed according to the cylinder head structure and manufacturing succession. The design of the high-pressure fuel line consists of three element factors, they are space strike, inner diameter and sealing type, unit pump system is used in the BF6M1013-28 engine, so the injection pump is separately mounted in the cylinder block which are linear with the fuel injector in the cylinder head respectively, thus, the shape of the high-pressure fuel line for each cylinder is identical, the length of run is 196 milimeter which is more simple than in-line pump system, distributor pump system and common rail system in the structure, and optimizes system performance; the inner diameter is decided according to the formula and production experience; the joint sealing type of high-pressure fuel line is designed as per the standards. The type of the fuel feed pump are determined by the fuel injection system, engine BF6M1013-28 uses separate rotor type fuel feed pump, predicting fuel supply volume and assembly performance is pursued in the design.Proceeding small-lot trail-manufacture to the production, and performance test to the BF6M1013-28 engine, the test results prove that the design of fuel supply system is wholly satisfied with the complete engine development target, including dynamics, economy and emission tests. Fuel supply system applying in complete vehicle, based on the requirement of dynamics and economy, generalized the requirement of the vehicle to it, including the requirement of low pressure fuel circuit permitted resistance force and compression force, the inlet-return fuel specified distance in fuel tank, the minimum distance from inlet port to the bottom of fuel tank, the position of manual fuel pump, the flow diameter of fuel pipe, the temperature of fuel, the volume of fuel return. In order to satisfy these requirements, the concrete design essentials in fuel tank assemble is summarized, the amount of fuel is calibrated, and proceeds matching tests in test vehicle to low pressure fuel circuit inner diameter, and determine the final design results.In accordance with CA1253P7K1L11T1 road test, the development target of fuel supply system, including dynamics and economy are validated. At the same time, it proves the design method that are established in the paper are correct.In this paper, based on research status of FAW R&D Center production, presents design method of fuel supply system of vehicles and engines, sets theoretical foundation and practicability for further research of the diesel engine fuel supply system.At present, the output of CA1253P7K1L11T1 matching BF6M1013-28 engine is about 1000 each month, the gross of production achieve 4000 up to now. The fuel supply system plays a important role in performance of the complete vehicle and the design method are validated.
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